Rising demand for fuels and potentially diminishing supplies of crude oil (or at least limits in or volatility in the capacity to manufacture fuels from crude oil) have spurred increased interest in the production of fuels from alternative sources.
Coal, natural gas and biomass can be converted to synthesis gas (generally composed of hydrogen and carbon monoxide) in accordance with known techniques. Synthesis gas can, in turn, be converted to liquid hydrocarbons by the well-known technique of Fischer-Tropsch catalysis, which has been utilized for the production of fuels for many years. See, e.g., M. Dry, High quality diesel via the Fischer-Tropsch process—A review, J. Chem. Technol. Biotechnol. 77: 43-50 (2001). Fischer-Tropsch catalysis, however, produces a mixture of alkanes, many of which are of lower molecular weight and unsuitable for use as liquid hydrocarbon fuels such as gasoline and diesel fuels.
Some examples of dual catalyst systems are described in R. Burnett and T. Hughes, Mechanism and Poisoning of the Molecular Redistribution Reaction of Alkanes with a Dual-Functional Catalyst System, J. Catalysis 31, 55-64 (1973) (See also U.S. Pat. No. 6,566,568 to Chen). These techniques have not been widely implemented. Accordingly, there is a need for new ways to convert lower molecular weight alkanes to higher molecular weight alkanes useful as liquid hydrocarbon fuels.